[postgis-users] ST_Buffer malfunction on LINESTRING

Paul Ramsey pramsey at cleverelephant.ca
Wed Aug 26 08:41:44 PDT 2020


Try some more recent versions. I'm finding with my very-fresh GEOS I'm getting a poly-with-hole, just as you are.
P.

> On Aug 26, 2020, at 2:58 AM, Michal Seidl <michal.seidl at gmail.com> wrote:
> 
> Hello,
> I am facing this malfunction of ST_Buffer. The result of closed LINESTRING buffer should be polygon with hole but regular polygon is returned?
> 
> I am using:
> POSTGIS="2.1.4 r12966" GEOS="3.4.2-CAPI-1.8.2 r3921" PROJ="Rel. 4.8.0, 6 March 2012" GDAL="GDAL 1.10.1, released 2013/08/26" LIBXML="2.9.1" LIBJSON="UNKNOWN" RASTER
> 
> This is the case
> ST_AsText(ST_Buffer(ST_GeomFromText('LINESTRING(-632707.74 -1143841.28,-632728.28 -1143828.04,-632761.31 -1143818.48,-632747.42 -1143835.92,-632727.41 -1143861.05,-632687.29 -1143893.42,-632587.04 -1143963.89,-632469.61 -1144047.39,-632439.8 -1144068.97,-632426.45 -1144083.11,-632422.85 -1144089.95,-632423.07 -1144099.75,-632426.7 -1144107.51,-632427.54 -1144108.41,-632426.4 -1144109.46,-632425.57 -1144108.56,-632411.95 -1144094.85,-632403.98 -1144087.66,-632393.94 -1144079.17,-632371.19 -1144059.68,-632381.11 -1144052.77,-632398.98 -1144062.1,-632407.15 -1144063.46,-632420.6 -1144058,-632457.53 -1144030.85,-632521.98 -1143975.36,-632585.23 -1143928.05,-632634.76 -1143892.41,-632627.84 -1143886.95,-632631.46 -1143883.96,-632637.6 -1143889.98,-632684 -1143856.57,-632707.74 -1143841.28)'), 0.001)) AS wkt_geometry
> 
> If I enlarge buffer distance to 0.01 result looks OK. Also if I change from default propeties to endcap=square join=miter helps?
> 
> Anu suggestions?
> 
> Thanks Michal S.
> _______________________________________________
> postgis-users mailing list
> postgis-users at lists.osgeo.org
> https://lists.osgeo.org/mailman/listinfo/postgis-users



More information about the postgis-users mailing list